Open Access research that is better understanding work in the global economy...

Better understanding the nature of work and labour within the globalised political economy is a focus of the 'Work, Labour & Globalisation Research Group'. This involves researching the effects of new forms of labour, its transnational character and the gendered aspects of contemporary migration. A Scottish perspective is provided by the Scottish Centre for Employment Research (SCER). But the research specialisms of the Department of Work, Employment & Organisation go beyond this to also include front-line service work, leadership, the implications of new technologies at work, regulation of employment relations and workplace innovation.

Abstract

Detailed knowledge of the dopant concentration and composition of wide band gap AlxGa1−xN layers is of crucial importance for the fabrication of ultra violet (UV) light emitting diodes (LEDs). This paper demonstrates the capabilities of wavelength dispersive X-ray (WDX) spectroscopy in accurately determining these parameters and compares the results with those from high resolution X-ray diffraction (HR-XRD) and secondary ion mass spectrometry (SIMS). WDX spectroscopy has been carried out on different silicon-doped wide bandgap AlxGa1−xN samples (x between 0.80 and 1). This study found a linear increase in the Si concentration with the SiH4/group-III ratio, measuring Si concentrations between 3×1018 cm−3 and 2.8×1019 cm−3, while no direct correlation between the AlN composition and the Si incorporation ratio was found. Comparison between the composition obtained by WDX and by HR-XRD showed very good agreement in the range investigated, while comparison of the donor concentration between WDX and SIMS found only partial agreement, which we attribute to a number of effects.